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Flashcards in Feed Related Deck (34)
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1
Q

What pH enhances hydrolysis of urea by urease

A

alkaline – Urea is basic

2
Q

What are the most susceptible species to urea

A

Ruminants and horses

3
Q

What percent of urea should be in feed

A

3% grain ration

1% total ration

4
Q

What age is more sensitive to urea and what age is more tolerant

A

Less than a year is more sensitive

3-6 wks are tolerant

5
Q

Urea is changed into ___ and ___ by ____

A

Changed into ammonia and CO2 by rumen microflora (urease)

6
Q

Fasting and dehydration ___ toxicity

A

Increase

7
Q

Diets low in ____ and ___ but high in ___ increase toxicity

A

Low in energy and protein but high in fiber

8
Q

Toxicity of urea is due to

A

ammonia

9
Q

Ammonia inhibits the ____ resulting in lack of energy and decreased cellular respiration

A

citric acid cycle

10
Q

Urea toxicosis chemistry panel

A

Ammonia
Lactate
Acidosis
BUN, K, P

11
Q

Time of onset of clinical signs for urea

A

30 min to 3 hr

12
Q

Clinical signs of urea

A

Restless, aggression, tremors, salivation, teeth grinding, bloat, ass in air
NO diarrhea
Convulsions and death in 1-2 hrs

13
Q

With urea toxicosis where should samples be taken from and how are they stored

A

Whole blood, rumen fluid, vitreous fluid

Frozen immediately

14
Q

What is the treatment for urea

A

Acetic acid or vinegar for ruminants every 4-5 hrs for 48 hrs

15
Q

What are ionophores used for

A

anticoccidial
growth promotor
efficiency of milk production
reduction of bloat/rumen acidosis

16
Q

what is the most common ionophore

A

monensin

17
Q

Which specie is most susceptible and least susceptible to ionophores

A

Horses most

Poultry least

18
Q

Ionophores are rapidly metabolized by ___ in the _____

A

P-450 oxidative demethylation enzymes in the liver

19
Q

Ionophores metabolize slower in the __ because

A

Horse because they have fewer oxidative demethylases

20
Q

What is the mechanism of action for ionophores

A

Disrupt membrane electrochemical gradients
Mainly highly energetic tissues (heart, skeletal, kidney)
Increased intracellular Na and Ca

21
Q

Ionophore clinical signs in the horse

A

Rapid onset

Anorexia, sweating, colic, incoordination, hyperventilation, tachycardia, death

22
Q

Ionophore clinical signs in other animals

A

Anorexia, diarrhea, weakness, respiratory impairment

23
Q

Ionophore lesions in horses

A

Mainly cardiac — pale muscle, white streaks

24
Q

Ionophore lesions in cattle and poultry

A

Skeletal and cardiac

25
Q

Ionophore lesions in sheep/swine/dog

A

Mainly skeletal

26
Q

Best samples to take for ionophores

A

FEED

GI content, liver, feces

27
Q

What enzymes are elevated with ionophores

A

CPK, AST, LDH, ALP

28
Q

With ionophores what in the serum is decreased in the first 12 hrs

A

Ca and K

29
Q

Which species are most susceptible to salt

A

Pig, Cattle, Poultry

30
Q

What does high Na do in the brain

A

Inhibits anaerobic glycolysis causing lack of energy to transport Na out – the trapped Na pulls in water causing cerebral edema

31
Q

Clinical signs of excess Na

A
Vomit, PU, met acidosis
Convulsions
Circling, pivoting, head pressing
Blindness/deafness
Inability to recognize/take in food/water
32
Q

Excess sodium signs in poultry

A

Depression, ascites, collapse

33
Q

Excess Na lesions

A

GI pinpoint ulcers

Fluid/edema systemically – CEREBRAL EDEMA

34
Q

What lesion is specific to pigs with Na excess

A

Eosinophilic meningoencephalitis